Reapply fix for Bug 860607 - fixing my own merge messup from last month - gnarf

Bug 860607 - Delete multiple SMS by calling mozMobileMessage.delete() directly. r=julienw
(cherry picked from commit cdc37c5b0580b0f97735555b3de5e1bdd9fda08f)

Conflicts:
	apps/sms/js/message_manager.js
(cherry picked from commit 12f80303011646bece5034e901429e3328d6c218)

Conflicts:
	apps/sms/js/message_manager.js